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31.
Macedo-Soares MF Itami DM Lima C Perini A Faquim-Mauro EL Martins MA Macedo MS 《The Journal of allergy and clinical immunology》2004,114(1):97-104
BACKGROUND: Chronic airway inflammation is a fundamental feature of bronchial asthma, which is characterized by the accumulation and activation of inflammatory cells, such as mast cells and eosinophils, that are tightly regulated by TH2 cytokines and chemokines. Recently, we demonstrated, in a murine model of asthma with immunosuppressed mice reconstituted with antigen-specific IgE or IgG1 antibodies, that IgE, but not IgG1, participates in potentiation of airway inflammation and induction of airway hyperreactivity (AHR). The IgG1 antibody, however, did not elicit passive cutaneous anaphylactic reactions, which was in contrast to IgE. OBJECTIVES: Because 2 types of murine IgG1 have been demonstrated with regard to anaphylactic activity, the present experiments were undertaken to determine the role of anaphylactic and nonanaphylactic IgG1 antibodies in the development of antigen-induced eosinophilia and AHR in this model. METHODS: Dinitrophenyl-conjugated, heat-coagulated hen's egg white was implanted in immunosuppressed mice reconstituted with anaphylactic or nonanaphylactic IgG1. Intratracheal challenge with aggregated dinitrophenyl-ovalbumin was performed on day 14, and lung inflammatory and mechanical parameters were evaluated after 48 hours. RESULTS: Our results demonstrated that reconstitution of immunosuppressed mice with anaphylactic IgG1 antibodies in contrast to nonanaphylactic IgG1 antibodies potentiates their ability to have pulmonary eosinophilic inflammation and AHR. IL-5 and eotaxin levels in bronchoalveolar lavage fluid from anaphylactic IgG1-reconstituted mice were also higher than those in nonanaphylactic IgG1-reconstituted mice. CONCLUSIONS: These results indicate that the anaphylactic property of murine IgG1 molecules is essential for their capacity to enhance lung eosinophilic inflammation and to induce AHR. 相似文献
32.
Seropositivity for and Intestinal Colonization with Entamoeba histolytica and Entamoeba dispar in Individuals in Northeastern Brazil 下载免费PDF全文
Lucia L. Braga Yacy Mendonca Clece A. Paiva Andrea Sales Andre L. M. Cavalcante Barbara J. Mann 《Journal of clinical microbiology》1998,36(10):3044-3045
In a slum community in northeastern Brazil 20% of a sample population was colonized with Entamoeba histolytica or Entamoeba dispar and 10.6% was colonized with E. histolytica alone. No correlation between seropositivity for anti-GalNAc lectin antibody and colonization was found. These results suggest that colonization does not necessarily produce immunity to reinfection. 相似文献
33.
Distinct Leishmania braziliensis isolates induce different paces of chemokine expression patterns 总被引:1,自引:0,他引:1 下载免费PDF全文
Teixeira MJ Fernandes JD Teixeira CR Andrade BB Pompeu ML Santana da Silva J Brodskyn CI Barral-Netto M Barral A 《Infection and immunity》2005,73(2):1191-1195
Inflammatory events during Leishmania braziliensis infection in mice were investigated. Large lesions were directly correlated with the inflammatory reaction but not with parasite burden. Different L. braziliensis strains induce different paces of chemokine expression patterns, leading to diverse cell recruitment and differential inflammatory responses. 相似文献
34.
Sputum Cytokine Levels in Patients with Pulmonary Tuberculosis as Early Markers of Mycobacterial Clearance 下载免费PDF全文
Rodrigo Ribeiro-Rodrigues Tatiana Resende Co John L. Johnson Fabiola Ribeiro Moises Palaci Ricardo T. S Ethel L. Maciel Fausto E. Pereira Lima Valderio Dettoni Zahra Toossi W. Henry Boom Reynaldo Dietze Jerrold J. Ellner Christina S. Hirsch 《Clinical and Vaccine Immunology : CVI》2002,9(4):818-823
Sputum and serum from patients with active pulmonary tuberculosis (TB), healthy purified protein derivative-positive adults, and patients with bacterial pneumonia were collected to simultaneously assess local immunity in the lungs and peripheral blood. To determine whether cytokine profiles in sputum from TB patients and control subjects were a reflection of its cellular composition, cytospin slides were prepared in parallel and assessed for the presence of relative proportions of epithelial cells, neutrophils, macrophages, and T cells. Gamma interferon (IFN-γ) in sputum from TB patients was markedly elevated over levels for both control groups. With anti-TB therapy, IFN-γ levels in sputum from TB patients decreased rapidly and by week 4 of treatment were comparable to those in sputum from controls. Further, IFN-γ levels in sputum closely followed mycobacterial clearance. Although detected at fourfold-lower levels, IFN-γ immunoreactivities in serum followed kinetics in sputum. TNF-α, interleukin 8 (IL-8) and IL-6 also were readily detected in sputum from TB patients at baseline and responded to anti-TB therapy. In contrast to IFN-γ, however, TNF-α and IL-8 levels also were elevated in sputum from pneumonia controls. These data indicate that sputum cytokines correlate with disease activity during active TB of the lung and may serve as potential early markers for sputum conversion and response to anti-TB therapy. 相似文献
35.
Production of type II heat-labile enterotoxin by Escherichia coli isolated from food and human feces. 总被引:8,自引:4,他引:8 下载免费PDF全文
B E Guth C L Pickett E M Twiddy R K Holmes T A Gomes A A Lima R L Guerrant B D Franco L R Trabulsi 《Infection and immunity》1986,54(2):587-589
Escherichia coli strains isolated in Sao Paulo, Brazil, from feces of patients with diarrhea and from food samples produced toxin(s) that was shown to be related both immunologically and genetically to the recently characterized type II heat-labile enterotoxin of E. coli. The new isolates of type II heat-labile enterotoxin-producing E. coli belonged to five different serotypes and did not represent a single clone. 相似文献
36.
Soluble factors released by Toxoplasma gondii-infected astrocytes down-modulate nitric oxide production by gamma interferon-activated microglia and prevent neuronal degeneration 下载免费PDF全文
Rozenfeld C Martinez R Figueiredo RT Bozza MT Lima FR Pires AL Silva PM Bonomo A Lannes-Vieira J De Souza W Moura-Neto V 《Infection and immunity》2003,71(4):2047-2057
The maintenance of a benign chronic Toxoplasma gondii infection is mainly dependent on the persistent presence of gamma interferon (IFN-gamma) in the central nervous system (CNS). However, IFN-gamma-activated microglia are paradoxically involved in parasitism control and in tissue damage during a broad range of CNS pathologies. In this way, nitric oxide (NO), the main toxic metabolite produced by IFN-gamma-activated microglia, may cause neuronal injury during T. gondii infection. Despite the potential NO toxicity, neurodegeneration is not a common finding during chronic T. gondii infection. In this work, we describe a significant down-modulation of NO production by IFN-gamma-activated microglia in the presence of conditioned medium of T. gondii-infected astrocytes (CMi). The inhibition of NO production was paralleled with recovery of neurite outgrowth when neurons were cocultured with IFN-gamma-activated microglia in the presence of CMi. Moreover, the modulation of NO secretion and the neuroprotective effect were shown to be dependent on prostaglandin E(2) (PGE(2)) production by T. gondii-infected astrocytes and autocrine secretion of interleukin-10 (IL-10) by microglia. These events were partially eliminated when infected astrocytes were treated with aspirin and cocultures were treated with anti-IL-10 neutralizing antibodies and RP-8-Br cyclic AMP (cAMP), a protein kinase A inhibitor. Further, the modulatory effects of CMi were mimicked by the presence of exogenous PGE(2) and by forskolin, an adenylate cyclase activator. Altogether, these data point to a T. gondii-triggered regulatory mechanism involving PGE(2) secretion by astrocytes and cAMP-dependent IL-10 secretion by microglia. This may reduce host tissue inflammation, thus avoiding neuron damage during an established Th1 protective immune response. 相似文献
37.
Marques da Silva SH Queiroz-Telles F Colombo AL Blotta MH Lopes JD Pires De Camargo Z 《Journal of clinical microbiology》2004,42(6):2419-2424
Paracoccidioidomycosis (PCM) is a systemic fungal disease that is particularly important among individuals living and working in rural areas of endemicity in Latin America. Detection of anti-Paracoccidioides brasiliensis antibodies is of limited value due to false-negative results. Detection of P. brasiliensis-gp43 circulating antigen is a practical approach for a specific diagnosis of the disease. In a previous study we described an inhibition enzyme-linked immunosorbent assay able to detect the 43-kDa P. brasiliensis antigen in sera of 100% of patients with the acute form of PCM and in 95.31 and 100% of patients with the chronic multifocal and unifocal forms of PCM. To investigate its potential application for the follow-up of PCM patients during treatment, antigen levels were monitored at regular intervals for up 8 to 12 months in serum samples from 23 patients. The results showed that treatment with itraconazole resulted in decreasing levels of circulating gp43 that were correlated with the reduction of anti-gp43 antibodies. It was also observed that by the end of 12 months of treatment gp43 levels were <5 microg/ml in all patients. 相似文献
38.
Chemiluminescent and flow cytometric analysis of gamma interferon preincubation on neonatal and adult rat polymorphonuclear leukocytes. 下载免费PDF全文
R R Wittler M M Lieberman D D Paine S L Muehlbauer J E Lima D M Sachanandani C A Pinney 《Clinical and Vaccine Immunology : CVI》1996,3(5):527-532
Gamma interferon (IFN-gamma) has multiple immunomodulating effects and has been postulated as a possible immunopotentiating agent for the prevention or treatment of neonatal infections. This report describes the effect of rat recombinant IFN-gamma on the oxidative burst activity and CD11b expression of neonatal and adult rat polymorphonuclear leukocytes (PMNL). Oxidative burst activity was assessed by chemiluminescence and dihydrorhodamine flow cytometry. Neonatal PMNL exhibited significantly less oxidative burst activity than did adult PMNL. IFN-gamma mildly enhanced the chemiluminescence response of PMNL from both the rat pups and adults, but this effect was not statistically significant when analyzed by a multivariate model of repeated-measures analysis of variance for both chemiluminescence and dihydrorhodamine flow cytometry. CD11b expression was also not significantly enhanced by IFN-gamma. 相似文献
39.
I. Tavares D. Lima 《Experimental brain research. Experimentelle Hirnforschung. Expérimentation cérébrale》1994,99(3):455-463
The location of neurons in the caudal medulla oblongata that project to the superficial or deep dorsal horn was studied in the rat, by means of retrograde labelling from confined spinal injection sites. The tracer cholera toxin subunit B was injected into laminae I–III (fuve rats) or I–V (three rats) at C4–7 spinal segments. Neurons projecting to the superficial dorsal horn were located in the dorsomedial part of the dorsal reticular nucleus ipsilaterally, the subnucleus commissuralis of the nucleus tractus solitarius bilaterally, and a region occupying the lateralmost part of the ventrolateral reticular formation between the lateral reticular nucleus and the caudal pole of the spinal trigeminal nucleus, pars caudalis, bilaterally. Neurons projecting to the deep dorsal horn, which were only labelled when laminae I–V were filled by the tracer, occurred in the dorsomedial and ventrolateral parts of the dorsal reticular nucleus and in the ventral reticular nucleus bilaterally. A few cells were located in the above described lateralmost portion of the ventrolateral reticular formation bilaterally and in the ventral portion of the ipsilateral cuneate nucleus. In the light of previous data demonstrating that dorsal horn neurons project to the dorsal reticular nucleus, the ventrolateral reticular formation, and the nucleus tractus solitarius, and that neurons in these three medullary regions are involved in pain inhibition at the spinal level, the descending projections demonstrated here suggest the occurrence of spino-medullary-spinal loops mediating the analgesic actions elicited in each nucleus upon the arrival of nociceptive input from the dorsal horn. 相似文献
40.
The development of Babesia equi in salivary glands of adult female Boophilus microplus was observed under a light microscope using semithin sections stained with toluidine blue. Engorged nymphs were obtained
from splenectomized foals experimentally infected with B. equi. As adults, they were then fed on rabbits for 5 days and the salivary glands of manually collected individuals were removed
at intervals of 24 h. Sporozoites were found in type III granular acini cells between the 2nd and 5th days following feeding
on the rabbits. Sporoblasts and sporozoites were observed in the same or adjacent acini cells in all the glands examined.
The formation of the sporozoites occurred following the multiple division of the sporoblasts through a process of radial budding
from the periphery of bodies resulting from multiple fission. Sporozoites were detected in smears of adult males stained with
Giemsa, between the 2nd and 5th days following feeding by the ticks. Adults of B. microplus, fed during the nymphal phase on foals with patent parasitemia, transmitted sporozoites of B. equi to a splenectomized foal. The role of B. microplus in the transmission and epidemiology of B. equi is discussed.
Received: 16 June 1997 / Accepted: 2 September 1997 相似文献